Annunciator with timed illumination means

ABSTRACT

An annunciator control system is provided having a momentary-on pushbutton switch to activate a doorbell, chimes or other audio signal means and a delay means to provide electric current to an illuminating device for a predetermined period of time after the switch is depressed. The illuminating means may be an ordinary incandescent lamp located in the pushbutton switch housing to illuminate the person activating the device or it may be a remotely located lamp such as an entrance way lighting fixture to illuminate the entrance for a fixed period of time after the system is activated.

United States Patent Gardner ANNUNCIATOR WITH TIMED ILLUMINATION MEANSDonald J. Gardner, 3741 Penbrook Lane #13, Flint, Mich. 48507 Filed:Aug. 17, 1970 Appl. No.: 64,344

Inventor:

US. Cl ..'...340/326, 337/88 Int. Cl. ..G08b 27/00 Field of Search..337/376, 88, 107, 64, 68, 100, 337/104, 120, 77; 219/505, 506;340/3661, 326,

References Cited UNITED STATES PATENTS 6/1964 Bagno ..340/ 3 30 9/1964Conigliaro ....340/326 5/1960 Slater ..337/88 10/1941 Luce ..337/88 [45]Mar. 7, 1972 2,439,766 4/1948 Weissman ..340/366.1 3,084,237 4/1963Mentzer ..337/88 1,828,321 10/1931 Hesse ..337/104 2,697,765 12/1954Little ..337/77 2,801,313 7/1957 Reynolds ..337/120 PrimaryExaminer-Harold Broome Attorney-Dennison, Dennison, Townshend & Meserole[57] ABSTRACT An annunciator control system is provided having amomentary-on pushbutton switch to activate a doorbell, chimes or otheraudio signal means and a delay means to provide electric current to anilluminating device for a predetermined period of time after the switchis depressed. The illuminating means may be an ordinary incandescentlamp located in the pushbut ton switch housing to illuminate the personactivating the device or it may be a remotely located lamp such as anentrance way lighting fixture to illuminate the entrance for a fixedperiod of time after the system is activated.

10 Claims, 9 Drawing Figures Patented March 7, 1972 3 Sheets-Sheet lmvzu'rons DONALD J. GARDNER ATTORNEYS Patented March 7, 1972 3,648,273

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INV Elis DONALD J. GARDNER Patented March 7, 1972 3,648,273

3 Sheets-Sheet 5 mvnm'ons DONALD J. GARDNER ATTORNEYS ANNUNCIATOR WITHTIMED ILLUMINATION MEANS This invention relates to improvements inannunciator systems such as doorbells or chimes of the type primarilyused in residential dwellings. It comprises a combination of a doorbellswitch, thermal delay switching means, lamp circuitry, and a thermistorto activate the thermal delay switch.

Prior art devices merely activate a bell or chime, or in the case of thepatent to WEISSMAN, U.S. Pat. No. 2,439,766, activate a lamp as long asthe pushbutton is depressed. When the prior art systems are activated atnight the occupant of the dwelling cannot normally tell who is at theentrance unless he turns on an exterior lamp, or in the case of anannunciator used to signal deaf or partially deaf persons, the signal isusually so brief due to being activated only while the button isdepressed that it is often not noticed by the occupant.

One objective of this invention is to overcome the above deficiencies ofprior art annunciator systems by providing a time delay means associatedwith the pushbutton switch which will provide current to an illuminatingmeans for a predetermined period of time and thereby illuminate theperson activating the system for a duration of time sufficient for theoccupant to identify who is at the door. Such system provides securityto the homeowner from unwanted callers and possible intruders.

Another object of the present invention is to provide a visual signalinside a residence for a predetermined period of time after the systemis activated to enable sufficient time for an occupant to recognize thesignal.

A further object of this invention is to provide an annunciatoractivation switch readily adaptable to currently installed annunciatorsystems which will provide current to existing illuminating means for apredetermined duration of time after the system is activated.

Another objective of the present invention is to provide an annunciatoractivation switch readily adaptable to currently installed annunciatorsystems wherein the switch housing contains a lamp controlled by a timedelay means to illuminate the area in front of the switch for apredetermined length of time after the switch is depressed.

A further objective of the subject invention is to provide anannunciator activation system which is readily adaptable to existingannunciator systems and is simple to install.

Another objective of the subject invention is to provide an annunciatoractivation system which provides the foregoing improvements and isefficient, reliable, and economical to manufacture and to install.

In the drawings:

F IG. 1, is a circuit diagram of an annunciator system in combinationwith the time delay and illuminating means of this invention;

FIG. 2, is a cross section through the side of the switch housing of oneembodiment of this invention revealing the momentary-on activationswitch, time delay means and illuminating means and schematicallyillustrating the interconnection between the power source and an audiosignal means;

F IG. 3, is a cross section through the top of the switch housingillustrated in FIG. 2;

FIG. 4, is a section through a portion of the switch housing assemblyshowing a second embodiment of the invention wherein the illuminatingmeans is remotely located;

FIG. 5, is a top cross section of an alternate embodiment of the switchassembly incorporating a modified activation and time delay switchingmeans affording protection against overheating of the thermistor;

FIG. 6, is a side cross-sectional view of the switch assembly embodimentillustrated in FIG. 5;

F IG. 7, is a top cross section of an alternate embodiment of the switchassembly incorporating a modified activation and time delay switchingmeans affording instant on operation of the illuminating means andincreasing the duration of time the illuminating means will beenergized;

FIG. 8, is a side view of the latching cam incorporated in theembodiment illustrated in FIG. 7; and

FIG. 9, is a front view of the latching cam incorporated in theembodiment illustrated in FIG. 7.

Considering the drawings in more detail, the schematic of F IG. 1illustrates the functional aspects of the invention. In the preferredembodiment of the invention current is supplied from the normalresidential electrical power source 10 to a stepdown transformer 11 andbell or chime 12 as in the normal residential annunciator or doorbellsystem. Momentaryon pushbutton switch 13 is used to control current flowbetween the secondary 14 of the transformer 11 and the activation coil15 of the aduio signaling device 12. A thermistor 16 is provided inparallel with the coil 15 of the audiosignaling device so that currentwill flow through the thermistor when the pushbutton 13 is depressed.The heat generated by electric current flow through the thermistor 16causes bimetal switch arm 17 to deflect and close a circuit at contact18. This provides a path for current from the transformer 11 through alamp l9, bypassing the pushbutton switch 13. Therefore, when the systemis activated, the lamp will remain illuminated after the pushbutton isreleased and will remain activated until such time that the bimetalswitch arm coolssufficiently to move away from contact 18.

FIG. 2 illustrates one embodiment of the invention wherein thecomponents comprising the improvements are contained within a switchhousing 20. The switch housing may be fabricated from a nonconductingmaterial such as plastic and is in the shape of a rectangular box openon the top side. A recess 21 is formed about the inner periphery of theopen side of the box to receive a translucent cover plate 22. Thetranslucent cover plate 22 has a bore 23 formed in it to receive themomentary-on pushbutton switch activation rod 24. The switch activationrod 24 has an enlargement 25 formed on one end to retain the pushbuttonactivating rod within the switch housing assembly 20. If desired, agrommet 26 may be provided in the bore 23 of the translucent cover plate22 to provide a longer bearing surface against the side of theactivating rod to ensure that it will not twist in the assembly. Locateddirectly below the pushbutton activating rod is a .l-shaped springcontact 30 which mates with L-shaped spring contact 31 when theactivating rod 24 is depressed to form the pushbutton contact 13 ofFIG. 1. Normally the spring contact arm 30 bears against the bottom ofthe activating rod 24 to hold it firmly in the grommet 26 provided inthe cover plate 22. The opposite end of this spring contact 30 issecured to the switch housing bottom panel 33 by a hollow rivet 34having a threaded bore through the center for receiving a wire-retainingscrew 35. Spring contact 31 is similarly fastened to the bottom panel 33of the switch housing 20 by a hollow threaded rivet 36 andwire-retaining screw 37. The thermistor 16 and bimetal element 17 aresecured in the switch housing by an L- shaped bracket 40 which issecured to the bottom panel 33 of the switch housing 20 by a hollowthreaded rivet 41 and wire retaining screw 42. The thermistor 16,bimetal element 17 and L-shaped bracket 40 are assembled together by ascrew 43 passing through a bore in all three elements and retained by anut 44 (see FIG. 3). Delay switch contact 18 is secured to the switchhousing lower panel 33 by a screw 45 which passes through a bore in thebottom panel to engage threads formed in a bore through hollow delaycontact 18. The lamp 19 is retained in the switch housing by reflector46 which as a tab 47 formed thereon to retain the lamp socket 48therein. The lamp socket 48 is a standard type having two electricalterminals. The reflector 46 is secured to the bottom panel 33 of theswitch housing 20 by one or more rivets 49.

In the embodiment illustrated in FIGS. 2 and 3 the electrical connectionbetween delay contact 18 and one terminal of the lamp base 48 isprovided by an internal wire 50 and the connection between the lamp l9and spring contact 31 is provided by an internal wire 51 connectedbetween the other terminal of the lamp base 48 and river 34. Theelectrical contact between thermistor l6 and spring contact 30 isprovided by an internal wire 53 connected between rivet 34 and aterminal means 54 secured to the thermistor by nut 44 but insulated fromthe nut 44 and screw 43 by an insulating sleeve 55 passing through thecenter of the thermistor and an insulating washer 56. The stepdowntransformer 11 is connected to the switch assembly via wire-retainingscrews 37 and 42 and the audio signaling means-12 is connected to theswitch assembly via wire-retaining screws 35 and 42.

FIG. 4 illustrates an alternate embodiment of the switch assemblywherein a remotely located lamp 60 such as a porch or hall light isconnected to terminal 18 via screw 45 and to spring contact 31 viaretaining screw 37. In this embodiment, the internal lamp 19 may or maynot be incorporated.

FIGS. 5 and 6 depict another alternate embodiment of the componentscontained within the switch housing comprising improvements which, inthe event an operator holds the pushbutton switch 13 depressed for anexcessive period of time, will prevent thermistor 16 from overheating.In this embodiment, spring contact 30 is replaced with spring contact 61composed of a single piece of flat conductive metal spring similar to 30except the contact end is bifurcated to form two arms, 62 and 63.Contact arm 62 serves the same function as contact arm 30 in thepreviously defined embodiment whereas contact arm 63 completes thecircuit through thermistor 16 via the conductor 64 which is attached tothe end of the bimetal element 17 via a nonconductive support means 65such that as thermistor 16 heats, it causes the bimetal 17 to deflectand close contact 18 the energizing current for thermistor 16 is therebyremoved due to the deflection of the bimetal away from contact arm 63even though contact arm 63 is held depressed. Contact arm 63 is formedso that it is below contact arm 62 due to the relative relationshipbetween contacts 31 and 64. The difference in position between contact62 and 63 and the pushbutton activation rod 24 is eliminated by thescrew 66 which is threaded through a tapped bore in contact arm 63 suchthat the activation rod 24 will contact switch arm 62 simultaneouslywith extension screw 66. In this embodiment contact 64 replaces theelectrical connection formed by wire 53 in the previous embodiment andterminal 54 is not used. However, the insulating sleeve 55 andinsulating washer 56 are retained to provide electrical insulationbetween contact arm 64 and screw 43 and nut 44. It should be noted thatFIG. 5 illustrates the bimetal in a partially deflected position. Whenthe bimetal is cool, the end of contact 64 through which the insulatedretainer 65 passes is located directly beneath spring contact arm 63.When sufficiently heated, the bimetal element 17 is flexed againstcontact 18. In this embodiment of the invention an external lamp 60and/or internal lamp 19 may be incorporated as previously described.

FIG. 7 depicts a further improvement of an alternate embodiment of thestructure illustrated in FIGS. 5 and 6 which eliminates the necessity ofholding the pushbutton switch 13 depressed until the bimetal element 17is heated sufficiently to close contact 18. This improvement consists ofthe addition of a latching cam 67 depicted in FIGS. 8 and 9.

The latching cam 67 is constructed of a conductive material and has athreaded bore along the longitudinal axis for receiving screw 66 suchthat it will be mechanically and electrically fastened to the pushbuttonside of contact arm 63. The latching cam 67 is cylindrical at the endadjacent to contact arm 63 and of a diameter equal to the width of thecontact arm. A tapered protrusion 68 extends from one side of thelatching cam body and forms a cam surface which has a detent 69 having aflat surface 73 perpendicular to the longitudinal axis of the latchingcam defining a shoulder. The radius 74 of the protrusion 68 above thedetent 69 is constant and greater than the radius at the base of theprotrusion.

In this embodiment contact arm 63 is positioned relative to contact arm64 such that when the pushbutton 13 is depressed the lower section ofthe cam surface 68 engages contact 64, completing the electrical circuitbetween contact arm 63 and the thermistor 16 as previously discussed.The slope of the cam surface 68 below the detent 69 is dimensioned suchthat as the pushbutton moves down, the latching cam 67 forces contact 64and the bimetal element 17 toward contact 18. The bimetal element 17engages contact 18 when the cam surface 68 has partially traversedcontact 64. As the latching cam 67 continues to move down the side ofcontact 64 it causes contact 64 and the bimetal element to flex so thatas the detent 69 of the latching cam 67 passes below contact 64, contact'64 slides across the flat surface 73 due to spring tension of thebimetalic element 17. The interaction of the spring tension of contactarm 63 and bimetalic element 17 holds the latching cam 67 in thedepressed position when the pushbutton 13 is released. The radius 74 isdimensioned to hold bimetalic element 17 in contact with contact 18 whenthe latching cam 67 is in the latched position, ensuring that thecircuit at contact 18 remains closed until the bimetalic element 17 isheated sufficiently to cause closure of the circuit due to thermalaction of the switch. As the bimetal element 17 heats it flexes awayfrom the latching cam 67 and draws contact 64 over the flat surface 73and out of the detent 69, releasing the latching cam 67 which returns tothe normally off position due to the spring action of contact arm 63.This opens the circuit to the thermistor 17, activating the time delayfeature of the switch assembly. This embodiment causes the bimetalicelement 17 to reach a greater temperature and thus increases the amountof delay.

I claim:

1. An annunciator system, comprising: an electrically driven audiosignal means, a normally open pushbutton switch means for selectivelyconnecting said audio signal means to a source of electrical power, athermistor electrically connected to the normally unenergized terminalof said switch means and in shunt relationship to said audio signalmeans, and a bimetallic heat responsive switch connected to saidthennistor and responsive to said thermistor to complete an electricalcircuit when heated after said switch member is closed and which willmaintain the circuit closed while heated.

2. In an annunciator system as defined in claim 1 and further including,a nonconductive housing mounting said switch means, a light-permeablecover on at least a portion of said housing and electrical illuminationmeans in said housing adjacent to said cover and operable when saidheat-responsive switch is closed for emitting radiant energy.

3. In an annunciator system as defined in claim 2, said pushbuttonswitch member comprising a first contact formed from a flat conductivespring secured at one end to said housing, a manually actuable switchactuator extending through said cover and adapted to deflect said firstcontact, a second contact formed from a flat conductive spring securedat one end to said housing, the other end of said second contact beingnormally spaced from but within the path of movement of said firstcontact and being engageable therewith when the same is deflectedthereby completing a circuit through said thermistor and said audiosignal means.

4. In an annunciator system as defined in claim 2 and further includinga reflector secured in said housing adjacent said illumination means forreflecting light toward and through said cover.

5. In an annunciator system as defined in claim 1, and further includinga nonconductive housing mounting said switch means, and electricalillumination means remote from said housing and electrically connectedto said switch means and operable when said heat-responsive switch isclosed.

6. In an annunciator system as defined in claim 1, and furtherincluding, a nonconductive housing mounting said switch means, a coveron said housing, said pushbutton switch member comprising a flatconductive spring member secured at one end to said housing, the otherend thereof being bifurcated forming a first and second contact arm, amanually actu' able switch actuator extending through said cover andadapted to deflect said first and second contact arms, a third contactformed from a flat conductive spring secured at one end to said housing,the other end of said third contact being normally spaced from butwithin the path of movement of said first contact arm and beingengageable therewith when the same is deflected thereby completing acircuit through said audio signal means, and a conductive stripmechanically and electrically secured to one terminal of saidthermistor, said bimetallic switch being mechanically and electricallysecured to the other terminal of said thermistor, said strip beingmechanically but not electrically connected to said bimetallic switchand being engageable by said second contact arm during deflectionthereof only when the bimetallic switch is in an unheated condition,thereby completing a circuit through said thermistor.

7. In an annunciator system as defined in claim 6 and further including;an electrical illumination means in said housing adjacent to said coverand operable when said heatresponsive switch is closed for emittingradiant energy, and a light-permeable section in said cover adjacent tosaid illuminating means.

8. In an annunciator system as defined in claim 7 and further includinga reflector secured in said housing adjacent to said illumination meansfor reflecting light toward and through said cover.

9. In an annunciator system as defined in claim 6, and further includingan electrical illumination means remote from said housing andelectrically connected to said switch means and operable when said heatresponsive switch is closed.

10. In an annunciator system as defined in claim 6 and furtherincluding, a conductive cam secured to said second contact arm forengaging said conductive strip when said

1. An annunciator system, comprising: an electrically driven audiosignal means, a normally open pushbutton switch means for selectivelyconnecting said audio signal means to a source of electrical power, athermistor electrically connected to the normally unenergized terminalof said switch means and in shunt relationship to said audio signalmeans, and a bimetallic heat responsive switch connected to saidthermistor and responsive to said thermistor to complete an electricalcircuit when heated after said switch member is closed and which willmaintain the circuit closed while heated.
 2. In an annunciaTor system asdefined in claim 1 and further including, a nonconductive housingmounting said switch means, a light-permeable cover on at least aportion of said housing and electrical illumination means in saidhousing adjacent to said cover and operable when said heat-responsiveswitch is closed for emitting radiant energy.
 3. In an annunciatorsystem as defined in claim 2, said pushbutton switch member comprising afirst contact formed from a flat conductive spring secured at one end tosaid housing, a manually actuable switch actuator extending through saidcover and adapted to deflect said first contact, a second contact formedfrom a flat conductive spring secured at one end to said housing, theother end of said second contact being normally spaced from but withinthe path of movement of said first contact and being engageabletherewith when the same is deflected thereby completing a circuitthrough said thermistor and said audio signal means.
 4. In anannunciator system as defined in claim 2 and further including areflector secured in said housing adjacent said illumination means forreflecting light toward and through said cover.
 5. In an annunciatorsystem as defined in claim 1, and further including a nonconductivehousing mounting said switch means, and electrical illumination meansremote from said housing and electrically connected to said switch meansand operable when said heat-responsive switch is closed.
 6. In anannunciator system as defined in claim 1, and further including, anonconductive housing mounting said switch means, a cover on saidhousing, said pushbutton switch member comprising a flat conductivespring member secured at one end to said housing, the other end thereofbeing bifurcated forming a first and second contact arm, a manuallyactuable switch actuator extending through said cover and adapted todeflect said first and second contact arms, a third contact formed froma flat conductive spring secured at one end to said housing, the otherend of said third contact being normally spaced from but within the pathof movement of said first contact arm and being engageable therewithwhen the same is deflected thereby completing a circuit through saidaudio signal means, and a conductive strip mechanically and electricallysecured to one terminal of said thermistor, said bimetallic switch beingmechanically and electrically secured to the other terminal of saidthermistor, said strip being mechanically but not electrically connectedto said bimetallic switch and being engageable by said second contactarm during deflection thereof only when the bimetallic switch is in anunheated condition, thereby completing a circuit through saidthermistor.
 7. In an annunciator system as defined in claim 6 andfurther including; an electrical illumination means in said housingadjacent to said cover and operable when said heat-responsive switch isclosed for emitting radiant energy, and a light-permeable section insaid cover adjacent to said illuminating means.
 8. In an annunciatorsystem as defined in claim 7 and further including a reflector securedin said housing adjacent to said illumination means for reflecting lighttoward and through said cover.
 9. In an annunciator system as defined inclaim 6, and further including an electrical illumination means remotefrom said housing and electrically connected to said switch means andoperable when said heat responsive switch is closed.
 10. In anannunciator system as defined in claim 6 and further including, aconductive cam secured to said second contact arm for engaging saidconductive strip when said second contact arm is depressed, a camsurface formed on said conductive cam adapted to deflect said conductivestrip and close said bimetalic switch, and a detent formed in said camsurface adapted to cooperate with said conductive strip to hold same camin a position maintaining deflection of said conductive strip andclosure of said bimetalic switch until said bimetalic switch heatssufficiEntly to disengage said conductive strip from said detent.